Filling Knowledge Gaps in Industrial Dust Emissions

Dust emissions from the smelter have long been a challenge for Sauda, an industrial town in Norway. Researchers from NORCE are collaborating with Eramet Norway Sauda to make the operation of the smelter virtually dust-free.

The air quality in Sauda is good, but house walls and garage doors are occasionally discoloured, most likely due to diffuse dust emissions from the plant.

– We want to uncover exactly where the dust originates and understand how it is transported in the air from the plant to the surroundings. This will enable us to identify and implement measures that reduce the burden which the dust poses to our neighbours, says Rune Dolmen, Managing Director at Eramet Norway Sauda.

NORCE researcher Hege Indresand is developing real-time measurements to monitor diffuse dust in Sauda. She has led several campaigns to characterize the dust in residential areas. Indresand and the plant work together to uncover where the dust originates.

Inside the Eramet plant, there are still some processes that produce dust. While emissions from chimneys are captured by filter housings and cleaning systems, diffuse emissions present challenges in mitigation. Such emissions include dust from wheel loader transport, from crushing processes, and from other material handling processes outdoors.

– We need to understand how dust travels in the air, how it affects neighbours and the environment, and exactly from where inside the plant it originates. This allows the industry to better manage its processes and find solutions to reduce the remaining emissions, says Indresand.

– Monitoring technology for diffuse dust has improved vastly in recent years, and we also understand more of the basic processes that create dust. This enables us to connect everything for a greater understanding, explains Indresand.

She combines dust measurements with meteorological data and statistical analyses. The goal is to build a comprehensive system that tracks the dust from its creation until it settles on infrastructure.

– Our goal is to provide a real-time overview that allows the industry to take measures accordingly, says Indresand.

For the smelter, it is crucial to reduce dust emissions. A series of measures and investments have already been made.

– Addressing the problems associated with dust is important for our relationship with our neighbours, but also for our employees. To ensure the long-term operation and development of the factory, it is important to have efficient and competitive manufacturing processes that secure jobs in our community, says Dolmen.

– We have a very efficient production of a product that the world needs. Yet, it is important that the production minimizes the burden on the environment and local communities. We appreciate neighbours who are proud of the plant and how it creates value for our community. We are actively participating in research programmes to find new and important information about our diffuse emissions, says Dolmen.

Several filter systems have been installed. They have had a very positive effect on total dust emissions.

– Our plant is large, and there are many outdoor activities. We need a better understanding of what kind of dust affects the surroundings the most. Research is also crucial to document which measures work, says Dolmen.

For Sauda, ​​this is about more than air quality. A dust-free environment means less maintenance, better well-being, and increased trust between the factory and residents.

– Our goal is zero dust emissions, says Dolmen.

Researchers believe that the plant can reduce emissions significantly within a decade. The ambition is to make Sauda a model for green industry.

– If we solve the dust problem in Sauda, we can solve similar problems for smelters or dusty processes in Norway and elsewhere in the world. Sauda can become an example for the world to follow, says Indresand.

She is regularly in Sauda to inspect the monitoring stations located in residential areas further up the hillsides in the town where the smelter sits by the fjord. If Sauda were a theatre, the smelter would be the stage.

The monitoring stations have been operational since 2017. Together with Eramet, NORCE has developed a special set of instruments that measures relevant dust in real-time.

– No one has put these instruments together to measure dust like this. By collecting data, we can help solve a big puzzle and a social problem, says Indresand.

She sees Sauda as an opportunity to find new truths that can benefit many industries.

– I am confident that the plant can achieve its goals, says Indresand.

– But acquiring the necessary knowledge is expensive – which is why it is important to cooperate on large-scale research projects to share cost and risk. We are now applying for a four-year innovation project that can strengthen research on dust issues in smelters and other dusty industries, such as quarries, mineral processing plants, and mines, and on construction sites.